The present application generally relates to a thermo-compensated silicon photo-multiplier with an on-chip temperature sensor.
A silicon photo-multiplier (SiPM) is a solid state detector with a matrix of avalanche photodiodes operated in a Geiger mode. SiPMs have been actively used in new photodetectors due to their excellent characteristics for detection of low intensities of light. The SiPMs can be used in physics experiments, aerospace applications and medical applications due to their compact size, good single photon counting resolution, high photon detection efficiency (e.g., up to 60%), high gain (e.g., up to 106), and insensitivity to magnetic fields. However, a limitation of SiPMs is that several important characteristics of the SiPM, such as gain, noise and photon detection efficiency, have a significant temperature dependence.
There are several approaches that can be used to design systems to mitigate the temperature dependence in SiPMs. For example, thermo-compensating systems can use temperature control, control of SiPM dark current and/or control of the SiPM bias voltage with respect to temperature in order to reduce the temperature dependence in SiPMs. The current thermo-compensating systems generally require additional resources, increase total power consumption and are not optimal for photodetectors that have many SiPM chips with different parameters such as breakdown voltage, leakage current and gain.